There is a US Region 1 release from Acorn Media. According to reviews the audio quality is substandard, which leads at least one reviewer to conclude that the actors speaking English in the Pakistani sequences have been dubbed. This is not an impression I obtained from watching the Region 4. The US release is also a PAL to NTSC conversion, so I would expect that the Region 4 is of better quality.
The reviews of the Region 1 are inconsistent, with one indicating that there are no extras, and the other stating that there are text filmographies and a text comparison between the series and the film version, and a short making-of featurette. Even if the extras are present the quality of the Region 4 transfer seems to be superior.
Warner Vision previously release this series on DVD in Region 4. Judging by the review of that release the reissue is an improvement. Specific faults noted in the video do not appear on the Umbrella disc.
The Region 4 release seems to be the best option at the moment.